EventCAT Conference + OBS Studio: How to Overlay Real-Time Translated Captions

Broadcast real-time translated captions from your offline event to online audiences using platforms like Zoom, YouTube Live, and more.

EventCAT Conference is a real-time interpretation solution for both small in-person meetings and large-scale conferences.

This guide shows how to stream your offline events with live multilingual captions using OBS Studio, a free virtual camera and broadcasting tool.

We’ll use Zoom as an example, but this setup also works with other platforms that support virtual camera input.

Problem Summary & Description

If you’re running an offline event and want to stream it online with real-time multilingual captions, EventCAT Conference offers a powerful Caption Overlay Mode. Using OBS Studio, you can broadcast these subtitles to your online meeting participants.

• This guide walks you through how to:

• Set up EventCAT Conference

• Enable Caption Overlay Mode

• Capture the caption screen using OBS Studio

• Broadcast it to Zoom (or other platforms)

Step 1: Start Your EventCAT Conference Session

1. Go to https://eventcat.com/conference and log in.

2. Click “Schedule” to create your conference room and session.

   • You can do this perfectly by reading the related articles below.

   • Related article: How to set up ‘EventCAT Conference room’

3. Allow microphone permissions.

   • Make sure to grant microphone access to your browser so it can capture audio from your event.

4. Confirm your audio input device,

   • EventCAT initially uses your system’s default microphone. If you’re using an external audio interface or another preferred device, double-check that it’s selected correctly. Once confirmed, click the Start Session button at the top right to begin your session.

5. Run a rehearsal first, then switch to Live Mode for your actual event.

• Before your event, make sure you’re in Rehearsal Mode and click Start Session to test that the translation appears correctly.

• On the day of your live event, switch to Live Mode before starting the session. This will activate your paid pass. The session will automatically end once the pass duration is used up.

• Related article: How to use ‘EventCAT Rehearsal Mode’

Step 2: Enable Caption Overlay Mode

1. Click ‘Live View’ on the left of your session screen to open the user page.

2. Go to the Settings icon (top right) and enable Caption Overlay.

3. When Caption Overlay Mode is activated, the latest generated text will appear in a green box with up to two lines.

   • This green box is pre-configured to mimic the typical appearance of subtitles seen in movies or YouTube videos.

   • It uses the OBS default green chroma key color: RGB(0,255,0) / #00FF00

After setting up Caption Overlay Mode, say anything to generate text. If the text appears within the green box within 2 seconds, the setup is correct.

Step 3: Set Up OBS Studio

1. Open OBS Studio and create a new Scene.

         2. Add a Display Capture in Sources.

Choose your monitor that displays the caption overlay.

           3. Adjust the capture area to only include the green subtitle box:

Hold Alt (Windows) or Option (Mac) and drag the red border to crop.

             4. Position the green area at the center bottom of the screen.

            5. Apply a Chroma Key filter:

Right-click your Display Capture > Filters > Add Chroma Key under Effect Filters.

• Set the key color to Green. If applied correctly, the green area will disappear, leaving just the subtitles.

• Before enabling the virtual camera, ensure the Output Type is set to its default setting. Then click "Start Virtual Camera" — you're now ready to broadcast to Zoom.

Step 4: Broadcast OBS Studio Screen to Zoom

1. In OBS, click Start Virtual Camera.

2. Open Zoom and join your meeting.

3. Set your video source to OBS Virtual Camera.

4. Once the OBS Studio screen appears in Zoom, you’re all set. Depending on your Zoom settings, the screen might appear mirrored.

This setup can also be used with YouTube Live, Google Meet (via OBS virtual cam), MS Teams, and other streaming platforms.

This setup can also be used with YouTube Live, Google Meet (via OBS virtual cam), MS Teams, and other streaming platforms.

Plans That Support Caption Overlay Mode

• Half-day Pass

• All-day Pass

• Customized Plan

• This feature is billed per Conference room. Contact us to activate it for your event. 

Proactive Tips

• Do a test stream before your actual event.

• Use OBS’s preview to confirm that captions are showing correctly.

• Pin your EventCAT tab to the taskbar for quick access during your session.

Additional Support

• Visit the EventCAT Help Center

• Or email us at contact@eventcat.com